Change all occurrences of text formatting
I brought a document in from another source and I want to make a Table of Contents for the document. The problem is that when Pages brought it in it named the particular formatting "Free Form*", Pages won't build a ToC from that formatting. How do I change all occurrences of "Free Form*" to something like "Heading 1". There are over 200 occurrences, so I would rather not do it one at a time if I can avoid it.
MacBook Pro (13-inch Late 2011), macOS High Sierra (10.13.1)